The present invention relates to a guide which can be mounted to the teeth of a saw blade, for guiding a file used to sharpen the blade's teeth.
U.S. Pat. Nos. 4,228,702 to Stewart et al.; 3,766,807 to Combs; 2,755,559 to Pearce; 1,806,222 to Ross; 827,623 to Finger; and 735,100 to Hormby are exemplary of patents which disclose guides for positioning and guiding a file during reciprocal movement of the file in relation to saw teeth.
The Hormby patent, for example, discloses a structure in which the guide uses a pair of rollers of conical configuration with the rollers being vertically adjustable in relation to a support mounted on a base structure. The patents to Finger and Ross disclose a carriage on which a file is mounted with the carriage being slidably mounted on a support rod. The Pearce patent discloses a file guide for a chain saw in which rollers are utilized to support and guide a flat file. The Combs patent discloses a guide in the form of a plate having a notched edge portion associated with the saw teeth and file. The Stewart et al. patent discloses a file guide for a chain saw utilizing oppositely disposed rollers engaging and guiding the file.
None of these patents, however, discloses an arrangement in which a pair of rollers are supported on each side of the saw and receive the file therebetween with the guide including filing angle and depth adjustments and a tooth spacing adjustment, with a handle on one end of the guide which enables the file guide to be stabilized and to rotate the saw to the next filing position.